Sam Brown begins to close gap with incumbent Sen. Jacky Rosen in battleground Nevada

In a new survey, Rosen defeated Brown 49% to 44% among all voters, according to a new AARP poll. 

Among the key demographic of voters 50 years or older, Brown beat the Democrat 49% to 46%. 

The new poll, which indicates a close race, comes after some expressed concerns over the Republican's position behind Rosen in recent surveys. While many Republican candidates in crucial states had already improved their stature against incumbent Democrats, Brown was still losing to Rosen by significant margins. 

Earlier in the month, a New York Times and Siena College Poll had Rosen besting Brown 49% to 40%. 

"The huge gaps between the Senate and presidential races in these states were never realistic," said Kyle Kondik, managing editor of Sabato's Crystal Ball at the University of Virginia Center for Politics. "At the same time, Democratic Senate candidates have generally had better margins than Harris in almost every competitive state."

"He could carry several GOP Senate candidates over the finish line," he said. 

Nevada Republican strategist Jeremy Hughes said, "Sam Brown has the momentum at the end of this race and is benefiting from a strong early vote performance by Republicans."

Republicans have appeared to turn out in larger numbers than Democrats in Nevada's early voting thus far, which is a departure from past elections, according to one veteran political journalist in the state. 

While noting that Republicans have an advantage in early voting "at a time when the Ds usually have one," Jon Ralston, the CEO and editor of The Nevada Independent, wrote. "If that gets larger, big trouble for Dems." 

Ralston further told Fox News Digital, "It is a surprising, unprecedented turnout pattern in a presidential year."

"Democrats have usually used early voting to bank votes, and the election is all but over by Election Day. Not this year. Mail ballots sent to everyone changes everything, and it also makes predictions very difficult."

"Nevadans are surging to the polls because they know we can do better. There is incredible energy on the ground, and working Nevada families are rallying behind Sam Brown's plan to lower prices, secure the border and make life affordable again. Nevadans have made it clear they are ready for a change, and the momentum is on our side," Brown campaign spokesperson Raegan Lehman said in a statement. 

A spokesperson for Rosen's campaign told Fox News Digital, "Nevada Senate races are always close and competitive, and our campaign is taking nothing for granted.

"We're confident that voters will ultimately re-elect Jacky Rosen, a bipartisan and independent problem solver who delivers for working families, and reject MAGA extremist Sam Brown, who wants to take away abortion rights, repeal the Affordable Care Act and gut Social Security and Medicare."

Her campaign additionally pointed to a late June poll, also by the AARP, that showed Rosen and Brown similarly five points apart at 47% to 42%. Brown led Rosen with voters 50 and over by 49% to 44% at the time. 

That poll interviewed 1,368 likely voters in Nevada between June 12 and 18. It also had a margin of error of plus or minus 4 percentage points for the sample of voters overall and plus or minus 3.5 percentage points for the over 50-year-old sample. 

The new AARP poll that showed the gap closing interviewed 1,368 likely voters from Oct. 8 to 15. It has a margin of error of plus or minus 4 percentage points for the sample of voters overall and  plus or minus 3.5 percentage points for the over 50-year-old sample.